Water pump cover - O ring

[borntolandhard]

I removed my radiator a few days ago and after reassembly, there's a slight leak from the water pump cover (I followed this video). I reused the old o-ring. And it also looked like the previous owner used some gasketing on the mating surface.

I bought a new o-ring from Honda today and am going to replace it this weekend. My question is: put it on dry? lube with silicone? something else? Any other suggestions to make this leak-free? Thanks

[froche]

Well I just replace my o rings at the water pump after adding an extension piece to allow the radiator to be moved out for a pooe boy.

Firstly I needed 2 orings, because I added the extension piece, normally you only need one. I didn't but the Honda O ring I bought 12 o rings from Global O rings. You can find them at globaloring.com. What I purchased was listed below

N2.00X046 2X46 METRIC O-RING 12 EA
N2.00X054 2X54 METRIC O-RING 10 EA
P10A/N70 JIS SIZE P10A METRIC O-RING 20 EA

They were really inexpensive, the 2x46 were 15 cents each (that's the size needed for water pump) the 2x54 are for the upper thermostat housing (I needed those because while there I had to remove that outlet to get the radiator off) and the small size is for the orings used on the exhaust air input (I removed mine) with shipping it came to 9.73 total!

one Honda Oring will cost about 5.00 plus 5.00 to ship!

On to the leak part.
On a brand new Honda orings work fine, on older Honda's they work fine but every surface needs to be clean and free of junk (old gasket cement, silicone, oil residue, etc and no scratches (surface scratches are ok).

I stuffed a plastic bag into the water pump without the outlet cover on it and used a putty knife (never use a knife to clean with) to clean it, followed by a rag wet with brake cleaner. Then I used a drill with a 3-m scrunge pad to clean the outlet cover and the used a small sculpting tool to clean off all the gasket material from the outlet (I had temporarily used a Moroso part from a big block Chevy as a spacer and o rings wouldn't seal it so I had to use gaskets and gasket stuff to seal) followed by brake cleaner to finish.

It sealed fine, probably just really cleaning all the old stuff off and really cleaning everything will let the new o ring seal fine. Reusing orings can sometimes works but after they are held in compression thay can take a 'set" and will not completely seal. Certainly if it is in an inaccessible spot I suggest using new ones.

As to using anything to seal them... don't use anything. I always use a tiny bit of grease around the o ring in 2 to 3 spots and that hold them in just fine, and will melt and 'dissapear".

Good luck

[winguyjo]

dry or with a thin film of silicone, your choice. as stated, it's crucial to have clean, smooth mating surfaces.

[WingAdmin]

Don't do it dry. It's critical that the O-ring not roll when the pump is inserted into its cavity, or it will leak.

Silicone can work. Don't use petroleum jelly or oil, as they can attack the O-ring. The best thing to use is actually KY-jelly or other glycerin/water-based "personal lubricant." It's very slippery, won't hurt the O-ring, and dissolves/evaporates in the coolant.

[borntolandhard]

For future reference for anyone who needs it...
I sanded both surfaces with 180 grit paper to remove all the old stuff on there, cleaned the channel with brake cleaner and a pick, used a brand new O-ring covered with a thin film of silicone grease, and it is now leak-free. Thanks.
The service manual doesn't give torque specs for water cover bolts so I put on about 25Nm

[WingAdmin]

For future reference for anyone who needs it...
I sanded both surfaces with 180 grit paper to remove all the old stuff on there, cleaned the channel with brake cleaner and a pick, used a brand new O-ring covered with a thin film of silicone grease, and it is now leak-free. Thanks.
The service manual doesn't give torque specs for water cover bolts so I put on about 25Nm

Anytime the service manual doesn't give torque specs for a specific bolt, you'll find the torque specs in the front of the service manual under "General Information" - the 1200 table is below:

GL1200 Standard Torque Values

[gc33]

Hey guys... I work in the mining industry here in Western Australia. There are few tips ivepi ked up from hv and lv fitters. When dealing with Orings I now use rubber grease.
Won't block anything up like a lump of silicon either...

[grospetit]

hello an old partique says: you met on the joint what goes on the joint when is intaller ,,, radiator = antifreeze----

[jurgenbuell]

i always use dish-washer soap on parts that have to seal a waterbased product (like coolant), only small amount. never had any problem.

[WingAdmin]

i always use dish-washer soap on parts that have to seal a waterbased product (like coolant), only small amount. never had any problem.

Dish soap is alkaline (which helps it cut through fat and grease) and will corrode and erode aluminum. It should never be used as an assembly lube on aluminum parts - so engine block, water pump cover, alloy wheels, etc. When used to lubricate alloy wheels before installing tires, it eventually causes pitting of the aluminum bead mating surface of the wheel which makes the wheels slowly lose air.